Property tax search: find your assessment and fight back

Last updated 2026-07-09

What does a property tax search actually show you?

A property tax search pulls your parcel record from your county's public database. The record shows the assessed value the assessor placed on your property, the prior year's assessed value, the tax rate applied, any exemptions already granted, and a payment history.

The assessed value is the number that matters most. Most states assess at a fixed percentage of market value. Maryland assesses at 100 percent of full cash value but phases in increases over three years ^[1]. Colorado assessors are required by statute to value residential property at its actual value as of the assessment date, then apply a fixed assessment rate set by the legislature ^[2]. For tax year 2023, Colorado's residential assessment rate dropped to 6.765 percent under Senate Bill 23-108's temporary relief package ^[9].

The search will not tell you whether that assessed value is accurate. That part is your job, and it starts with pulling comparable sales yourself.

A few fields trip people up. "Assessed value" and "taxable value" are not the same thing in every state. After exemptions like homestead or senior freeze programs come out, the taxable value can drop a lot. Read both lines before you panic.

How do you find your property tax assessment online?

Every county in the U.S. keeps public property tax records, though the search interface varies wildly. Here is the fastest path in each scenario.

By address. Go to your county assessor's or auditor's website and look for a search bar labeled "property search" or "parcel search." Type your street address. Most modern county portals return results instantly. If yours has no working search, your state's department of revenue often runs a statewide lookup.

By parcel number. Your parcel number (sometimes called an APN, account number, or tax ID) appears on your tax bill or deed. It is the most reliable search key because addresses have formatting quirks.

By owner name. Most counties allow owner-name searches but return big result sets. Useful when you are researching a neighbor's assessment for comparison.

For Maryland, the State Department of Assessments and Taxation (SDAT) runs a statewide real property search at https://sdat.dat.maryland.gov ^[1]. You can look up any address in any Maryland county and see the full assessment record, including the three-year phase-in schedule.

For Colorado, each county assessor runs its own portal. The Denver, Arapahoe County, and Jefferson County tools follow a similar layout but are separate systems. Your county assessor website is the authoritative source. The Colorado Division of Property Taxation keeps a county directory at https://cdola.colorado.gov ^[2].

Here are five large counties with clean, reliable public portals:

County	State	Portal type	Parcel search available
Los Angeles County	CA	County Assessor portal	Yes [3]
Cook County	IL	Assessor + Treasurer split	Yes [4]
Maricopa County	AZ	County Assessor portal	Yes [5]
San Diego County	CA	County Assessor portal	Yes [6]
Bexar County	TX	Central Appraisal District	Yes [7]

Once you have your record pulled, screenshot it or save the PDF. That snapshot is your baseline for any appeal.

For readers in specific large metros, we have county-by-county guides: Los Angeles County property tax, Cook County tax assessor tax bill, Maricopa property tax, and San Diego property tax.

What do the numbers on your assessment record mean?

Most assessment records show several value lines, and people confuse them constantly. Here is what each one means.

Land value. The value the assessor assigned to your lot alone, without any buildings. In cities this can be the majority of total value.

Improvement value. The assessed value of everything built on the lot: the house, garage, sheds, pools. This is usually where errors live. Wrong square footage. Wrong bathroom count. A finished basement the assessor counted when it is actually studs and concrete.

Total assessed value. Land plus improvements. In states that assess at a fraction of market value, multiply this by the state's equalization ratio to get the implied full market value. In a 100 percent valuation state like Maryland, this number should directly reflect what the assessor thinks the house would sell for.

Taxable value. Assessed value minus exemptions. If you have a homestead, senior, or disability exemption, you see it deducted here.

Tax levy / effective tax amount. Taxable value multiplied by the mill rate. One mill equals $1 of tax per $1,000 of taxable value. A mill rate of 12 on a $300,000 taxable value means a $3,600 annual bill.

If any of those first three lines is wrong based on observable facts (wrong square footage, a bedroom count mismatch, a structural problem the record ignores), that is your strongest appeal argument. Physical errors are far easier to prove than a pure market-value disagreement.

How do you appeal a Maryland property tax assessment?

Maryland runs a three-level appeal system, and the deadlines are hard. Miss one and you forfeit that level.

Level 1: Supervisor's Appeal. When SDAT mails your Notice of Assessment (usually December or January), you have 45 days from the notice date to file a written appeal with the local SDAT office ^[1]. This is an informal review. You present your evidence to an assessment supervisor. No filing fee. SDAT guidance says you can submit comparable sales, a recent appraisal, or a list of physical errors in your property record.

Level 2: Property Tax Assessment Appeals Board (PTAAB). If you lose at the Supervisor's level, you appeal to the local PTAAB within 30 days of the Supervisor's decision ^[10]. The PTAAB is a three-member board. Hearings stay informal, but you need actual evidence, more than frustration.

Level 3: Maryland Tax Court. If PTAAB rules against you, you have 30 days to appeal to Maryland Tax Court, a formal administrative court ^[10]. At this stage you almost certainly want an attorney, or at least a licensed appraiser giving a formal opinion of value.

Start at the SDAT portal ^[1] to confirm the exact value being appealed and to download the property characteristics SDAT used. That property data card is the first document you bring to any hearing.

The single most common Maryland appeal mistake is missing the 45-day window on the initial notice. Notices go by mail. If you moved, mail forwarding does not extend the deadline. Check SDAT's portal now and then if you are unsure whether a new assessment cycle has run.

Evidence that works in Maryland. Sales of comparable homes within the past 12 months that closed below your assessed value. PTAAB and SDAT supervisors respond well to three to five clean comps with clear adjustments for size, age, and condition. A licensed appraisal carries more weight but runs $300 to $600. For most residential appeals, the comps alone win if the gap is obvious.

Maryland reassessment cycle. Maryland reassesses each property once every three years on a rolling basis, splitting the state into three groups ^[1]. The tax year 2025 group 1 counties had new notices mailed around January 2025. Check SDAT to confirm which group your county falls in and when your next reassessment date hits.

How do you appeal a Colorado property tax assessment?

Colorado's appeal timeline is tighter than Maryland's. Get it wrong and you wait two years for the next reappraisal cycle.

The Notice of Valuation. Colorado county assessors mail Notices of Valuation (NOVs) on or before May 1 in reappraisal years ^[2]. The 2023 and 2025 years are reappraisal years. The 2024 and 2026 years are off-years with generally no new valuation unless you made structural changes.

Protest deadline: June 1. You have until June 1 of the reappraisal year to file a written protest with your county assessor ^[2]. That is about 30 days from the May 1 mailing. Some counties accept online protests; others require a paper form or in-person filing.

Assessor's response: August 15. The assessor must send you a Notice of Determination by August 15 ^[2]. If you get nothing, under Colorado law your protest counts as denied.

Board of Assessment Appeals (BAA) or District Court. If you lose or get a partial win, you can appeal to the BAA (a state-level administrative tribunal) or straight to district court. The BAA filing deadline is 30 days from the Notice of Determination ^[2]. BAA hearings run more formally, and you exchange evidence in advance.

Colorado Revised Statute Section 39-5-122 sets the assessor's duty to value property, and C.R.S. Section 39-8-106 governs the protest process ^[2]. The statute reads: "The assessor shall consider the information presented by the taxpayer and, if warranted, change the valuation" ^[2].

The assessment rate change matters for your math. The legislature temporarily cut the residential assessment rate from 7.15 percent to 6.765 percent for tax years 2023 and 2024 under SB 23-108 ^[9]. So even if your assessed value held steady, your taxable value dropped a little. But if your actual value jumped 30 to 50 percent in the 2023 reappraisal (which it did across the Front Range), the rate cut did not offset the increase. That is why the 2023 and 2025 protest seasons saw record filing volumes in metro Denver.

Evidence for a Colorado protest. Colorado assessors use a mass appraisal model tied to a specific assessment date, June 30 of the year before a reappraisal year. For 2025 values, the reference date is June 30, 2024. Your comps need to be sales that closed within 18 months of that date to count ^[2]. Pull them from the county assessor's own sales file or from a public MLS record. The BAA and the courts weight arm's-length sales far above neighbor opinions or Zillow estimates.

For readers in metro Denver, Jefferson County, or Arapahoe County, your county assessor's portal is the starting point. The Colorado Division of Property Taxation publishes the annual Abstract of Assessment, showing median residential values by county, useful context for judging whether your county's values ran hot ^[2].

What evidence makes a property tax appeal actually win?

The strongest single piece of evidence in almost any residential appeal is a closed arm's-length sale of a comparable property that sold for less than your assessed value. "Arm's length" means a willing buyer and seller with no family relationship, no foreclosure pressure, and no odd terms.

Here is a rough hierarchy of evidence by persuasive weight at most appeal boards:

1. A licensed appraisal from a state-certified appraiser valuing your property as of the assessor's valuation date. 2. Three to six comparable sales you have adjusted for square footage, age, condition, and amenities. 3. A recent listing price well below assessed value (weaker, because listings are not closed sales). 4. Photos and repair estimates documenting physical condition the assessor ignored. 5. A printout showing factual errors in the assessor's property data card (wrong bedroom count, wrong square footage).

Tackle factual errors first. Assessors correct them fast, and the value reduction does not need a formal hearing at all. Call or email the assessor's office, send your documentation (a floor plan, permit records, photos), and ask for an administrative correction.

For comparable sales research, the most reliable free sources are your county assessor's own sales search tool, your state's recorded deed database, and public MLS data if you have access. Zillow's "recently sold" filter and Realtor.com's sold listings work as a starting point, but always verify against the county record.

One common trap: using comps that are not truly comparable. A 1,400 sq ft ranch and a 2,200 sq ft two-story are not comps without heavy adjustment. Boards dismiss sloppy comparisons fast. Do the adjustment math, even roughly, and show your work.

How do appeal deadlines compare across major states?

Missing a deadline is the number-one reason appeals die before they start. The table below covers the initial protest or appeal deadline for several major states. These are the dates by which you must file with the first-level reviewer, usually the assessor or a local board.

State	Initial deadline	Who you file with	Typical notice mailed
Maryland	45 days from notice	Local SDAT office	December/January [1]
Colorado	June 1 (reappraisal years)	County Assessor	On or before May 1 [2]
Texas	May 15 or 30 days from notice	Appraisal Review Board	April/May [7]
California (LA County)	November 30	Assessment Appeals Board	July/August [3]
Illinois (Cook County)	Varies by township	Cook County Assessor	Varies [4]
Arizona (Maricopa)	April 25	Assessor	February [5]
Georgia	45 days from notice	County Board of Assessors	Spring [8]

None of these deadlines are soft. Counties rarely grant extensions once the window closes. Put the deadline in your calendar the day you open the notice.

For readers in the Southeast, our Gwinnett County tax assessor, Cherokee County tax assessor, Coweta County tax assessor, and Madison County tax assessor guides cover the Georgia 45-day process in detail.

Should you hire a tax agent or do it yourself?

Here is the honest answer, not the diplomatic one.

For most residential appeals, you do not need to hire anyone. The evidence you need (comparable sales, your property record, photos) is public. The Level 1 hearing in Maryland and the protest stage in Colorado are built to be accessible to homeowners without a lawyer. The assessors know it.

A contingency firm makes sense in a few cases: you have a complex property (mixed-use, income-producing, unusual construction), the value gap is large enough that even a 25 to 40 percent contingency fee still leaves you ahead, or you genuinely have no time to research comps and build documentation.

It does not make sense for a standard single-family home, a clear and obvious overassessment that three comparable sales would fix, or a case where the firm would collect fees even though you would have won on your own.

The contingency model means firms typically take 25 to 40 percent of your first-year tax savings. On $1,500 of annual savings, that is $375 to $600 for work you could do in two to four hours. If you want to keep the full amount, the TaxFightBack DIY appeal kit walks through comp selection and documentation step by step.

One good middle ground: pay a licensed appraiser $300 to $600 for a formal appraisal letter and present it yourself. You get professional-grade evidence without the ongoing contingency cut.

What are the most common errors in property tax records and how do you spot them?

Pull your parcel record and compare every field against what you know is true about your home. These are the errors that show up most often, and the ones assessors fix without a formal hearing.

Square footage errors. The assessor's data often comes from permit records or a mass appraisal model, not a physical measurement. If your home is 1,650 sq ft and the record says 1,900, you are paying tax on 250 sq ft that does not exist. Measure your home, check your original building permit or survey, and submit the correction.

Bedroom and bathroom count. A three-bedroom home recorded as four gets a higher value. Plain data-entry error, and common.

Finished vs. unfinished basement. Finished basement space is typically valued at 50 to 75 percent of above-grade space. An unfinished basement logged as finished adds value that should not be there.

Lot size. Less common, but it happens. Check your survey or deed.

Condition rating. Assessors assign condition codes (excellent, good, average, fair, poor). If your roof is shot, the HVAC dates to 1987, and the kitchen has not changed since the Clinton administration, a "good" rating is wrong. Photos and contractor estimates help here.

Exemptions not applied. Your homestead, senior, or veterans exemption may be missing if you recently bought, recently turned 65, or recently became eligible. Check the taxable value line against the exemptions you applied for.

Pulling your record and checking these fields takes about 20 minutes. It is the fastest return on your time in the whole property tax game.

How do exemptions change your search results and your tax bill?

Exemptions reduce your taxable value before the mill rate applies. They do not reduce your assessed value, which is why people check their assessment record, see the same big number, and assume an exemption failed when it actually worked.

Maryland's Homestead Tax Credit caps how much your taxable assessment can rise in any single year. For most Maryland counties the cap is set locally, not by the state, and ranges from 0 to 10 percent annually ^[1]. The credit does not cut your base assessment; it limits the yearly growth of the taxable portion. If you bought recently and are not yet enrolled, file at https://sdat.dat.maryland.gov to register. The credit is not automatic on a new purchase.

Colorado's Senior Property Tax Exemption exempts 50 percent of the first $200,000 of actual value for qualifying seniors (age 65 or older, owned and occupied for 10 years) ^[2]. That works out to roughly $676 in tax savings at the statewide average mill rate, though the real number varies by county.

Many exemptions need annual renewal or a one-time application that never got filed. Check your county's exemption database or call the assessor's office to confirm what is on your account. It is a five-minute call worth hundreds of dollars a year.

How do you use your property tax search results to build a comp-based appeal?

Once you have your assessed value from the property search, answer one question: did similar homes in your area sell for less than what the assessor says your home is worth?

Here is the practical process.

Step 1: Know your assessor's value date. In Maryland, assessors set value as of January 1 of the reappraisal year ^[1]. In Colorado, it is June 30 of the year before a reappraisal year ^[2]. Your comps should be sales that closed within 12 to 18 months of that date.

Step 2: Define comparable. Same general neighborhood or subdivision, within 20 percent of your home's square footage, similar age (within 10 to 15 years ideally), similar style (ranch vs. two-story matters). Adjustments for differences are fine, but keep them modest and logical.

Step 3: Pull at least four to six comps. Use the county assessor's sales database, public deed records, or a real estate agent's MLS pull. Record the sale price, square footage, lot size, bed/bath count, and sale date for each.

Step 4: Calculate implied value per square foot. Divide each comp's sale price by its square footage. Average those rates. Multiply by your square footage. If the result comes out meaningfully below your assessed value (10 percent or more is a common threshold worth pursuing), you have a case.

Step 5: Document everything. Print the comp records. Annotate the differences from your home. Build a one-page summary showing the calculation. That summary is your exhibit at the hearing.

The TaxFightBack appeal kit has a pre-built spreadsheet template for exactly this comparison, which saves about an hour of formatting. The underlying math is simple enough to do in any spreadsheet.

For readers in markets like St. Louis or the Chicago suburbs, our St. Louis County personal property tax and Lake County property tax guides include county-specific comp search instructions.

Frequently asked questions

How do I find my property tax assessment online for free?

Go to your county assessor's or auditor's website and use the parcel search tool. Enter your street address or parcel number. Every county in the U.S. keeps public property records at no charge. For Maryland, the statewide portal is at sdat.dat.maryland.gov. For Colorado, use your individual county assessor's site; the Colorado Division of Property Taxation at cdola.colorado.gov links to all 64 counties.

How do I appeal a Maryland property tax assessment?

File a written appeal with your local SDAT office within 45 days of receiving your Notice of Assessment. Present comparable sales or a recent appraisal showing the assessed value tops market value. If the supervisor denies you, you have 30 days to appeal to the Property Tax Assessment Appeals Board (PTAAB), then 30 more days to reach Maryland Tax Court. Missing any deadline forfeits that level.

How do I appeal a Colorado property tax assessment?

File a written protest with your county assessor by June 1 of a reappraisal year (odd years: 2025, 2027, and so on). The assessor must respond by August 15. If denied or partially denied, you have 30 days to appeal to the Colorado Board of Assessment Appeals or district court. Use comparable sales from within 18 months of June 30 of the prior year as your primary evidence. The deadline is firm; there are no extensions.

What is the Colorado property tax assessment appeal deadline?

June 1 of any reappraisal year (2025, 2027, and so on). Notices of Valuation go out on or before May 1, giving you about 30 days. If the assessor denies your protest by August 15, you then have 30 days to file with the Board of Assessment Appeals. These dates come from Colorado Revised Statute Section 39-8-106.

What is the Maryland property tax appeal deadline?

45 days from the date on your Notice of Assessment. Maryland SDAT typically mails notices in December and January. The 45-day window is calendar days, not business days. After the supervisor's decision, you get 30 days to appeal to the PTAAB, and another 30 days after PTAAB to reach Maryland Tax Court. The initial 45-day window is the one most homeowners miss.

How often does Maryland reassess property?

Every three years, on a rolling cycle. Maryland splits its jurisdictions into three groups and reassesses one group each year. Once reassessed, any increase in taxable value phases in over three annual increments instead of hitting all at once. Check the SDAT portal for your county's group assignment and your property's last reassessment date.

What is Colorado's residential assessment rate right now?

For tax years 2023 and 2024, the Colorado legislature temporarily set the residential assessment rate at 6.765 percent under Senate Bill 23-108, down from the prior 7.15 percent. For 2025 and beyond, check the Colorado Division of Property Taxation at cdola.colorado.gov for the current rate, since the legislature revisits this periodically. The rate applies to actual value to produce the taxable value your mill levy multiplies.

Can I appeal my property taxes if I just bought the house?

Yes, and your purchase price is strong evidence. If you paid less than the assessed value in an arm's-length deal that closed within the assessor's valuation window, that sale price is arguably the best available evidence of market value. File the appeal using your closing disclosure as a supporting exhibit. Maryland and Colorado both let new owners appeal right after receiving a notice.

What property tax records can the public access for free?

In nearly every U.S. county, the following are public: assessed value, taxable value, exemptions on file, payment history, property characteristics (square footage, bedroom count, year built), and the recorded deed. Transfer prices are also public in most states. Only a few states (Kansas is a notable example) do not disclose sale prices on the deed. For most comp research, everything you need is free from county portals.

How do I know if my property tax assessment is too high?

Pull your assessed value from the county portal and compare it to recent sales of similar homes nearby. If three or more genuinely comparable properties sold within the past 12 to 18 months for materially less than your assessed value (typically 10 percent or more), you likely have a case. Also check the assessor's data card for factual errors: wrong square footage, bedroom count, or finished area are common and fixable outside the formal appeal.

How much does a property tax appeal cost to file yourself?

Filing the initial protest or appeal with the assessor or first-level board is free in Maryland, Colorado, and most other states. There is no fee at the assessor or PTAAB level in Maryland, and no fee to file a Colorado protest with the county assessor. If you escalate to Maryland Tax Court or the Colorado Board of Assessment Appeals, expect a nominal fee (often $15 to $50). A licensed appraisal, if you choose to get one, runs $300 to $600.

What happens if I win my property tax appeal?

The assessor or board cuts your assessed value to the amount your evidence supports. Your county then recalculates the tax bill at the lower value. If you already paid at the higher rate, most counties issue a refund check or credit the next billing cycle. In Maryland, a successful PTAAB or SDAT appeal adjusts the current-year bill and, if the three-year phase-in already started, may reset the base for future years.

Can I search another owner's property tax assessment?

Yes. Property tax records are public in all 50 states. You can search by address or owner name on your county assessor's portal and see the assessed value, taxable value, and exemptions for any parcel. This is exactly how you research comparable properties for your own appeal: pull three to six neighbors' records, note their assessed values per square foot, and compare to yours.

Does a property tax search affect my credit or trigger a reassessment?

No. Searching your own or a neighbor's property tax record on a county portal is a public records lookup. It does not show up on any credit report and does not flag your property for reassessment. Reassessments come from the county's regular cycle, a sale, or a building permit, not from public record searches.

Sources

1. Maryland State Department of Assessments and Taxation (SDAT), Real Property portal and appeals information: Maryland assesses at 100 percent of full cash value, phases in increases over three years, mails notices December/January, and provides a 45-day initial appeal window to the local SDAT office.
2. Colorado Division of Property Taxation, Colorado Department of Local Affairs: Colorado assessors value residential property at actual value as of June 30 prior to the reappraisal year; NOVs mailed by May 1; protest deadline June 1; assessor responds by August 15; C.R.S. 39-8-106 governs protests.
3. Los Angeles County Assessor's Office, public property search portal: Los Angeles County offers online parcel search with assessed value, ownership, and payment records; initial appeal deadline is November 30.
4. Cook County Assessor's Office, online property search: Cook County Assessor provides property record search by address or PIN; appeal deadlines vary by township.
5. Maricopa County Assessor's Office, property search portal: Maricopa County provides public parcel search; initial appeal deadline is April 25 annually.
6. San Diego County Assessor/Recorder/Clerk, property search: San Diego County maintains public online property assessment records accessible by address or parcel number.
7. Bexar Appraisal District, property search portal: Bexar County Central Appraisal District provides free online parcel search; Texas protest deadline is May 15 or 30 days from notice, whichever is later.
8. Georgia Department of Revenue, Property Tax Division: Georgia property owners have 45 days from the notice of assessment to appeal to the county Board of Assessors.
9. Colorado General Assembly, Senate Bill 23-108, residential assessment rate temporary reduction: SB 23-108 temporarily reduced Colorado's residential assessment rate to 6.765 percent for tax years 2023 and 2024, down from 7.15 percent.
10. Maryland General Assembly, Tax-Property Article, Section 14-509 through 14-513, appeal procedure: Maryland Tax-Property Article establishes the three-level appeal structure (supervisor review, PTAAB, Maryland Tax Court), with 30 days to appeal from the supervisor to PTAAB and 30 days from PTAAB to Tax Court.